The present invention relates to a waveguide junction circulator designed for a high-frequency, high-power application and having a resonance cavity in which there is disposed a plurality of spaced and cooled superposed metal plates covered with ferrite discs and wherein outside the resonance cavity there is a magnet system which generates a magnetic field oriented perpendicularly to the ferrite discs.
Such a waveguide junction circulator is disclosed in IEEE Transactions on Magnetics, Vol. Mag-17, No. 6, November 1981, pages 2957-2960. This circulator is designed for a maximum high-frequency power of 250 kW at an operating frequency of 500 MHz and has a transmission loss of about 0.2 to 0.4 dB and a relatively narrow bandwidth of about 0.64% of the operating frequency so that the circulator reacts with great sensitivity to power fluctuations. Moreover, this prior art waveguide junction circulator has very large dimensions. It therefore requires an extremely high magnetic field which can be generated only with an expensive and large-volume electromagnet.